Long ago, the Seven Days of Fire, a war/cataclysm occurred. Humanity released the God Warriors and they destroyed nearly everything. Most of the world is dominated by poisonous fungal forest inhabited by bizarre insects, with desert dominating most of the rest of things. There are many small countries, each scheming against the others. Nausicaa is the princess of the Valley of the Winds. She loves animals, is expert with her glider, and is willing to risk her life for her people. Late one night, a huge Tolumekia plane crashes in the Valley of the Winds with something in its cargo hold...

An important thing to add, though, is that there are two editions (at least) of this anime around in the United States. One is a fansub which lets the original through rather well. The other, which was the official release, was The Warriors Of The Wind. It is a hideous dub job, which rips the storyline to shreds. That release was the reason that Miyazaki didn't want anyone to touch a translation of Princess Mononoke until Neil Gaiman convinced him that he would do the Right Thing with it.

Also note that this story is available as a much longer and slightly different manga.

Finally, the soundtrack on this anime is excellent, particularly the Interchange with the Ohmu theme.

Kaze no Tani no Nausicaa is set in the future, after a holocaust has devastated the earth. Humans live at a low technological level in a world on the edge of poisonous jungles filled with mutated animals. Although some machines remain from before the holocaust, most of them are clearly falling apart and, without any new technology, humanity seems to be slipping back into a fairly primitive lifestyle. Nausicaa (Zandra), the main character, is a princess in the Valley of the Winds. She finds herself involved in war, as certain groups attempt to revive old technology they don't really understand and threaten to destroy the earth again.

Nausicaa was popular when it first appeared as a serial in the magazine Animage, but was much more popular as an animated film. In fact it is definitely one of the most, if not the most, popular animated movie ever. It has been translated into English as Warriors of the Wind, but the translation is terrible, the editing worse, and the final result an embarassment to the original.

Personally, I thought the movie was quite a success in its English version. But perhaps I am biased; I grew up watching the movie, and probably could not tell the difference between what was good and bad film-wise. Now it's more of a cherished childhood memory, of which I can see no flaws. You'll have to watch it and decide for yourself.

It should be noted that the manga version is much, much better, mainly because its story is much longer and doesn't have a contrived happy ending. The manga started 1982 and ended 1994, while the anime was already released 1984. It has over 1000 pages.

In fact, Hayao Miyazaki himself was not satisfied with the anime's ending, and one motivation in making Mononoke Hime was to do better.